So I was reading a thread (here CSX Runaway Train - #8 by CJL_Railfan) and someone brought up a good point: When 8888 began to run away from the engineer, why didn’t the alerter go unchecked and apply the penalty brake. Well, according to the AI overview on Google, because the independent brake, not the automatic brake, was applied, this disabled the alerter. Assuming this is true, and taking it with the obligatory grain of salt, why didn’t the alerter go unchecked and stop the locomotive? This seems like it would be a glaring safety issue, one that could be fatal (8888 was stopped without injuries or fatalities as far as I am aware, but it had molten phenol in at least one tank car, I think two, which could have been really bad if the train had derailed and leaked everywhere) Thanks for any information anyone has on this.
My understanding is that the independent brake was applied and that that disabled the alerter. This also meant that 8888’s brake shoes were burned up by the time the incident was over. It’s not often that a locomotive has its brakes applied and is still throttled up.
Yes, I am aware of the application of the independent brake, but why exactly did that disable the alerter? and wouldn’t the brake shoes have, in theory, not burned out before the alerter went off had it not been disabled? Isn’t it like 30-45 seconds for the alerter period?
It disabled the alerter because they are interlocked, if I recall correctly–which is a good idea in all situations except this one. Such was the design choice.
Yes, that must have not been a good design choice in this scenario then…
According to the Wiki page for the incident, all the brake shoes on 8888 had been completely burned off by the heat, since they had been applied all throughout the runaway trip. The loco is still in service as of 2026, but is now renumbered as 4389 and rebuilt into a SD40-3 with a different cab type.
Yes, but wouldn’t the alerter, had it not been disabled by the application of the independent brake, not have been tripped before the brake shoes were worn off?
Potentially.
There is ‘logic’ that is built into the Alerter system. The Alerter is triggered by an absence of operating a specific Alerter button, operating the throttle, operating the dynamic brake, operating the automatic (train brake) or operating the independent (locomotive) brake.
When the Independent is applied - the ‘logic’ is that the Engineer is in control of the Independent Brake Valve and is actively managing the operation of the train.
The fact that the train continued on, with the Independent APPLIED, it is evident that the Independent WAS NOT applied with sufficient force to be able to STOP the movement, which WAS the engineer’s intent.
The Alerter system WAS NOT designed to protect against an engineer that wanted to use the Independent so that he could dismount the locomotive to throw a switch, with the intentions of reboarding the locomotive and continuing the train’s normal run.
The Engineer performed an action that the Designers had figured would never happen.
When designing systems to be ‘idiot proof’ the world will always find an idiot that will perform the swiss cheese collection of actions to defeat the design.
The old ‘Dead Man’ pneumatic switch, if some weight was not used to keep the pedal depressed’ would have stopped the train and not given the Engineer the opportunity dismount/throw switch/remount.
I’ve come across an alerter that would go off every 15 seconds, even when stopped with the independent brake set. To disable the alerter, the reverser had to be centered. With the reverser centered, the auto start/stop wanted to shut the locomotive down every 60 seconds.
As I remember, there was no override for the auto start/stop. Only moving the reverser to forward or reverse. This was on an old Canadian Pacific SD40-2, one of the “draper taper” style, that somehow got to be our leader. It’s the only one I recall coming across with this setup.
This was on a below zero night about 22 years ago. We were stopped short of a broken rail at a crossing in northern Iowa. The trip up the night before found us stopped at a broken rail at the same crossing. The difference was one break was south of the crossing, the second north of the crossing. Both breaks were in the crossing signal circuit, and the ABS circuit, so we had warning and were able to stop short both trips. Both times resulted in a 2 to 3 hour wait for MOW to come and fix the rails.
Jeff
Ah, makes sense